EXT4_FEATURE_RO_COMPAT_DIR_NLINK and the directory size.

["Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>]

Steps:
[root]# more /root/largedir 
i=65000
mkdir /mnt/tmp/test/
cd /mnt/tmp/test/
while [ $i -gt 0 ]
do 
        mkdir $i
        i=$(expr $i - 1)
done

# /root/largedir
# cd /mnt/tmp/test
# rm -rf *
# cd ..
# ls -al 
drwxr-xr-x  1 root root 1380352 Feb 12 07:15 test
# e2fsck -fv /dev/sda7
# ls -al 
drwxr-xr-x  2 root root 1380352 Feb 12 07:15 test


So e2fsck fix the link count. But the size is not updated. If i try to
run the script again, i get 

EXT4-fs error (device sda7): ext4_find_entry: reading directory #187681
offset 0
attempt to access beyond end of device
sda7: rw=32, want=17582522464, limit=19551042
attempt to access beyond end of device
sda7: rw=32, want=32620150800, limit=19551042
attempt to access beyond end of device
sda7: rw=32, want=32620150800, limit=19551042



Also after running fsstress fsck fails with zero size directory on
powerpc. I am finding directories with 

i_links_count == 1
i_blocks == 0

I missed to check whether the l_i_blocks_hi was having some value.

-aneesh